1. Field of the Invention
The invention relates to a pressing device for producing compacts from source material in powder form, in particular pulverized nuclear reactor fuel. The device has a die-plate contained in a platen and a bore associated with a ram, for receiving source material powder. It also has a filling shoe disposed at a movable arm, which shoe can be displaced over the platen, and applied against the platen, for filling source material powder into the die-plate bore. The filling shoe has an outflow opening directed toward the platen with a filling aid means and is connected by a hose to a reservoir for source material powder provided with a metering means.
2. Description of the Prior Art
Such a pressing device is already on the market. A jolting grid is disposed in the filling shoe of this commercially available pressing device, which as a filling aid means helps to fill the source material powder into the die-plate bore. The reservoir for source material powder is an open hopper with a flat slide as metering means for proportioning the source material powder supplied to the filling shoe.
However, the jolting grid in the filling shoe of this pressing device causes the escape of considerable amounts of source material powder at the seal which the filling shoe has toward the platen. Further, the transfer of source material powder from a storage or transport can into the open hopper causes intense dust formation, which likewise leads to losses of source material powder. Such losses occur, moreover, at the slide with which the open hopper is equipped for metering the source material powder supplied to the filling shoe.
These losses are of particular importance especially when processing pulverized nuclear reactor fuel such as UO.sub.2 or UO.sub.2 /PuO.sub.2 powder, as such fuels are not only very expensive, but also toxic and radioactive.
This is true in particular of plutonium-containing pulverized nuclear reactor fuels, which, to avoid toxic and radioactive load, are handled by operators in so-called glove boxes, the interior of which is sealed dustproof from the external environment.
Since the commercially available pressing device shows a dust formation and escape of powder at the filling shoe which are too great for the processing of pulverized nuclear fuels, this pressing device, when set up and operated in a glove box, causes considerable cleaning work to be done in this glove box, which work recurs regularly. In the handling of plutonium-containing pulverized nuclear reactor fuels, such dust formation may lead to exposure of the operators to a heavy radiation load.